Reciprocating compressors cylinders

Hartwick, W Power Requirement and Associated Effects of Reciprocating Compressor Cylinder Ends, Deactivated by Internal By-Pas.sing, ASMS 75-DGP-9, New York, NY American Society of Mechanical tine neens, 1975. 

Figure 12-17B. Effects of clearance volume on performance efficiency of reciprocating compressor cylinder (valve design effect). (Used by permission Livingston, E. H. Chemical Engineering Progress, V. 89, No. 2, 1993. American Institute of Chemical Engineers, Inc. All rights reserved.)...

Engine drivers are well adapted for reciprocating compressor cylinders, direct connection to power generators, direct or through gear connection to fans, centrifugal compressors, pumps, etc. ... 

The piston rod used in a reciprocating-compressor cylinder can fail if overstressed. The stress experienced by the piston rod is a direct function of the AP developed by the cylinder. That is because on one side of the piston, we have the suction pressure and on the other side of the piston, we have the discharge pressure. The AP times the area of the piston is therefore the force acting on the piston. Excessive force will break the piston rod. 

FIG. E-36 Large gas engine (ten cylinders) with bullt-on reciprocating compressor cylinders. (Source Cooper-Bessemer Reciprocating.)... 

This standard could be adapted to the fuel compressor for the natural gas to be brought up to the injection pressure required for the gas turbine. Covers the minimum requirements for reciprocating compressors and their drivers used in petroleum, chemical, and gas industry services for handling process air or gas with either lubricated or nonlubricated cylinders. Compressors covered by this standard are of moderate-to-low speed and in critical services. The nonlubricated cylinder types of compressors are used for injecting fuel in gas turbines at the high pressure needed. Also covered are related lubricating systems, controls, instrumentation, intercoolers, after-coolers, pulsation suppression devices, and other auxiliary equipment. 

The reciprocating compressor is generally in the lower flow end of the compressor spectrum. Inlet flows range from less than 100 to approximately 10,000 cfm per cylinder. It is particularly well-suited for high-pressure service. One of the highest pressure applications is at a discharge pressure of 40,000 psi. Above approximately a 1.5-to- i pressure ratio, the reciprocating compressor is one of the most efficient of all the compressors. 

A unique feature of the reciprocating compressor is the possibility of multiple services on one compressor frame. On a multistage frame, each cylinder can be used for a separate gas service. For example, one cylinder may be dedicated to propane refrigeration, while the balance of the cylinders may be devoted to product gas. 

Another feature necessary to the reciprocating compressor is cylinder cooling. Most process compressors are furnished with water jackets as an integral part of the cylinder. Alternatively, particularly in the smaller size compressors, the cylinder can be designed for air cooling. 

Figure 9-4. Terminology for analysis of a one-cylinder reciprocating compressor.

The gas testing described will apply to all compressors with casings. For the reciprocating compressors, the gas test, as specified by API 618, is applied to the cylinder. The test is used automatically only when gas... 

A basic item on the reciprocating compressor is the lubricated cylinder. The vendor will need guidance from the user advising whether lubrication can be used. 

A reciprocating compressor is a positive-displacement machine in which the compressing and displacing element is a piston moving linearly within a cylinder. Figure 10-1 shows the action of a reciprocating compressor. 

Figure 10-2. High-speed reciprocating compressor frames and cylinders. [Courtesy of Dresser-Rana Company.)...

Reciprocating compressor capacity may easily be adjusted by changing compressor speed, changing compressor cylinder clearance, unloading compressor cylinder inlet valves, recycling gas from unit discharge to unit suction, or a combination of these methods. All these methods may be accomplished either manually by the operator or automatically by the control panel. 

End view showing male and female rotors and slide valve on an 85-ton intermediate compressor. The robust design of the Series R compressor can ingest amounts of liquid refrigerant that would severely damage reciprocating compressor valves, piston rods, and cylinders. (Used by permission Cat. RLC-DS-2, Aug. 1995. The Trane Company.)... 

Figure 12-16D illustrates the type of reciprocating compressor performance problems that can develop from various mechanical details. To maintain peak efficiency in a compressor cylinder, a pressure-time indicator card of the cylinder during operation can be quite helpful in pointing to a problem and its nature. ... 

Piston displacement is the actual volume of the cylinder displaced as the piston travels its stroke from the start of the compression (condition (1)) to the end of the stroke (condition (e)) of Figure 12-12 expressed as fF of volume displaced per minute. Displacement values for specific cylinder designs are available from the manufacturers, Table 12-6. Neerken is a useful reference. Reciprocating compressors are usually rated in terms of piston displacement, which is the net volume in ft per minute displaced by the moving piston. Note that the piston does not move through the clearance volume of Figure 12-12 therefore this volume is not displaced during the stroke. 

Figure 13-1E. A computer facility performs dynamic simulation and analysis of reciprocating compressor installations such as this two-cylinder compressor. Interactive pulsation and mechanical analysis ensures trouble-free operation. (Used by permission Southern Gas Association s Gas Machinery Research Council.)...

Figure 14-4A. Oscillogram shows variation of current to a synchronous motor driving a reciprocating compressor, The compressor is two-cylinder, horizontal, double-acting, and operates at 257 rpm. Line A is the envelope of the current wave. Difference B-C is current variation. Value B-C divided by the rated full load current is the percentage of current variation. (Used by permission Oscarson, G. L. E-M Synchronizer, 200 SYN 52, p. 11. Dresser-Rand Company.)...

Figure 14-33. Gas engine driven parallel compression cylinders in process gas plant service. Note that the front side of gas engines are on the right with high-pressure compressor cylinders extending horizontally left. Also note the suction side pulsation drums on top of compressor cylinders, mid-way. (Used by permission Cooper-Cameron Corporation, Reciprocating Products Division.)...

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